Hard exclusive pion leptoproduction

TL;DR

This paper analyzes hard exclusive pion leptoproduction using the handbag approach, highlighting the importance of transversely polarized photons and transversity GPDs, with results aligning well with recent experimental data.

Contribution

It demonstrates that the handbag approach with transversity GPDs and twist-3 pion wave functions effectively describes experimental cross sections and asymmetries.

Findings

Strong contributions from transversely polarized photons are indicated by recent measurements.

Handbag approach results agree with experimental cross sections and asymmetries.

Predictions for other pseudoscalar meson channels are discussed.

Abstract

In this talk it is reported on an analysis of hard exclusive leptoproduction of pions within the handbag approach. It is argued that recent measurements of this process performed by HERMES and CLAS clearly indicate the occurrence of strong contributions from transversely polarized photons. Within the handbag approach such gamma*_T -> pi transitions are described by the transversity GPDs accompanied by twist-3 pion wave functions. It is shown that the handbag approach leads to results on cross sections and single-spin asymmetries in fair agreement with experiment. Predictions for other pseudoscalar meson channels are also briefly discussed.8 pages